In controls, the lateral free wall regions had a greater baseline εcc than the septal regions. In DMD patients, Δεcc was consistently greater in magnitude in the lateral free wall regions when compared to the Δεcc of the septal regions (Figure 1). MDE was consistently detected in these same lateral free wall regions.

Changes in εcc show that the regions with greatest contractility in control subjects (the lateral free wall) are the most susceptible to injury in DMD patients, as exemplified both by the greatest reduction in regional εcc and the development of MDE in those regions.